Timer for ignition systems



o. F; TALLMAN ET AL TIMER FOR `IGNITQN SYSTEMS sep-a 22, 1925. 1,554,693

Filed Aug. 23, 1924 Tf@ .JHeq zfids,

v BY WMZ( ATT NEY.

Patented Sept. 22, 1925.

UNITED STATES OSCAR FINLEY TALLMAN, WILLIAM PAUL KIMBROUGI'I, AND LOUISJAMES REYNOLDS,

?TENT OFFICE.

0F SHERMAN, TEXAS.

TIMER FOR IGNITION SYSTEMS.

Application filed August 23, 1924. Serial No. 733,825.

To all whom t may concern:

Be it known that we, OSCAR FINLEY TALL- MAN, YVILLIAM PAUL KIMBROUGH,and Lonis JAMns REYNOLDS, citizens of the United States, residing atSherman, in the county of Grayson and State of Texas, have invented newand useful Improvements in Timers for Ignition Systems, of which the`following is a specification.

This invention relates to timers for ignition systems of internalcombustion engines, and particularly to timers of that type embodying arotary member carrying a springpressed brush adapted for engagement withspaced contacts carried by a ring of insulated material mounted withinthe timer casing or shell.

One object of our invention is to provide a timer having a novelconstruction of pressure spring for the brush, which spring is ofconsiderable length and devoid of angles or interlocking connections inits movable parts liable to cause rapid fracture from crystallization orother causes, and which spring has a self-locking connection with therotor collar, thereby dispensing' with the use of auxiliary fasteners,the construction of the spring further ensuring its free movements atall times.

A further object of the invention is to provide a novel and simpleconstruction of rotor for supporting and guiding the brush and spring,and which serves to positively guide the brush in its movements and holdthe spring from displacement, and which will effectually prevent thebrush or spring from becoming clogged with grease to any such extent asto interfere with their movements.

A still further object of the invention is to provide a construction ofspring which will permit of the use of a comparatively long brush blockof copper, ensuring better electrical engagement with the fixedcontacts, avoiding the necessity of using a steel brush or an excessiveamount of lubricant, liable to cause pitting and carbonization of theparts and imperfect engagement between the brush and stationarycontacts.

lVith these and other objects in view, theinvention consists of thefeatures of construction, combination and arrangement of parts,hereinafter 'fully described and claimed, reference being had to thelaccompanying drawing, in which:

Figure 1 is a side elevation of our improved timer looking toward theouter side thereof and with the cap or cover removed.

Figure 2 is a central vertical section taken through the device on aline at right angles to its axis.

Figure 3 is a central section through the device taken parallel with itsaxis on the line 3 3 of Figure 1.

Figure 4 is a detail section on the line 4 4 of Figure 3.

Referring now more particularly to the drawing, 1 designates the endplate of the timing gear box of a timer of the character described, 2the rotary timer shaft, 3 the timer casing or shell detachably connectedwith the plate 1, 4 a removable cap or cover normally closing the openside of the shell, and 5 a spring or like fastener for holding the cap 4in position, the same being secured to a post 6 projecting from thehead 1. The shell 8 is provided as usual with an internal lining or ring7 of insulating material in which are embedded the spaced stationarycontacts 8 of the ignition mechanism.

A rotor 9 of novel form is provided in acordance with our invention tocarry the timer brush 10. This rotor 9 is formed of a single casting andcomprises a hub or sleeve 11 carrying at its inner side a circularflange 12 giving a proper bearing and balancing action in the rotationof said rotor. A second flange or wall 13 is arranged outside thisflange 12 in spaced relation thereto and to the outer end of the sleeve11 and is connected with the flange 12 by spaced transverse walls 14,the flange 13 and Walls 14 forming with a component part of the flange12 a radial guide chamber or guideway 15 to receive the brush 10 andhold it from displacement.

The brush 10 comprises an oblong rectangular solid block, of like format each end, whereby it may be reversed, end for end, if desired in theevent that one end should become improperly worn and it is desired topresent a new surface for action. This block has its sides formed toslide between the flanges 14, its inner edge sliding in engagement witha groove 16 in the fla-nge 12 and its outer edge sliding in contact withthe flange or Wall 13, whereby an accurate guide motion of the block isensured. The walls 14 are of comparatively short radial depth andpositioned adjacent to the outer peripheries ot the flanges 12 and 13,thus providing a transverse opening 17 extending completely through theguideway between the walls 141 and the sleeve 11.

A pressure spring 18 is provided tor toreing the brush 10 outwardly intocontact with the surface ot the insulating ring 7' and the stationarycontacts 8i This spring is ot' novel form and made ot flat spring metal,the inner portion ot the spring being` bent to provide a circular coilv19 surrounding the sleeve 11, andA the outer portion ot' the coil beingshaped to produce an incomplete spiral coilA 20. The coil 19 closelyembraces the sleeve 11 and the inner end of the spring forming oneterminal ot this coil is provided witlr an inbent tongue 21 to engage agroove or recess 2:2 inA the sleeve, whereby through the contractileenergy oli the coil 2O and locking engagement ot' the tongue 21 with thegroove 22, the spring is .tired to the sleeve 11 in a secure mannerwithout the use ot auxiliary fastenings. The opposite end 23. of thespring 18, forming the terminal of the coil 20, extends through the slot17 and bears against the inner end of the brush 10, the coilI 2O thusacting a pressure coil, the end 23 of which is movable in said slot, forpressing the brush outwardly into contact with the surface oit the ring7 and the contacts 8 'for proper operation of the rotor for a timingact-ion in the working of the device.

The operation ot the device willbereadily understood 'from the foregoingdescription, taken in connection with the d 'awing, by those versed inthe art, and it will be seen that a timer brush construction is providedconsisting oit only. three simple and rugged elements, to wit, the rotorwith. integral parts, the brush block and a :flat coiled spring actingon the block. Dueto the construction of'this rotor and 'torni ot thespring employed, a spring having an acting portion movable through awide range ot surface motion is produced and means provided whereby theworking portion ot' the spring is rendered devoid olf angles orinterlocking` connections liable to cause rapid crystallization,breakage or impairment olf the working action of the spring. Thedescribedconstruction ot' the spring further provides for itsapplication to the rotor without the use of auxiliary iastenings, andowing to the torm of the working portion 20 ot the spring, and its widerange of motion, it is not liable to be clogged by grease, so that aproper working action ot the brush is at all times ensured. This springalso Ienables a.

brush formed ot' a solid block ot copper to be used, and which is ofconsiderable wearing length, ensuring long life and better electricalconductivity and, as the wearing action ot such metal on the insulatingring 7 and contacts 8 is much less than that ot steel or other hardmetal, the necessity ot treqnently replacing the timer shellv or casingis avoided. The use of a copper brush also allows the contact surfacesto keep clean and dry, as the necessity for oil or other lubricant isavoided. or reduced to the very minimum, avoiding pitting,crystallization and other objections causing imperfect tiring incidentto the use ot oil or grease tor lubricating purposes. Therefore, as thecontact suri'aces will always keep dry and clean, the hotter spark willbe furnished, making the car start easier and run better and smoother.

Another advantage is that when it becomes necessary to renew the contactbrush all that is required is to remove the timer case, liit out thecontact brush, insert a new one, and replace the timer case, it notbeingl necessary to remove the brush holder or rotor, wherebyconsiderable time and labor is saved over timers ot' ordinaryconstruction. Having thus lully described our invention, we claim ln atimer, a rotary shaft, a disk lixed to the shai't and having a centralsleeve projecting laterally from its outer tace and embracing the shaft,a` radial guideway carried by the sleeve and shaft, said guideway including an inner wall formed by a radially recessed portion oft' thebody ot the disk, an outer wall extending radially 'trom the diskparallel with. said inner wall, and' opposite transverse wallsconnecting said inner and outer walls outwardly beyond the trans versecenter of the gui'deway, said guideway being open at its sides betweenthe inner edges oi said transverse walls and the periphery o'l` thesleeve, the said sleeve being provided with a notch in a side thereo'lat right angles to the guidewaya brush movable in said guideway, and ahat metal spring having a substantially circular inner portion embracingthe sleeve andy a spiral outer portion lyingy beyond the sleeve, one endof said spring constituting a terminal of said circular portionextending into and lhaving' an interlocking engagement with said notch,and the other end oit' said spring constituting a tree terminal ot saidspiral portion, said tree end terminal being arranged to bear upontheinner end o'l the brush and extending across the guideway and throughthe open sides thereor' and itreely movable in two directions, bothlongitudinally and transversely of said gnideway.

In testimony whereotl we aiflix our signatures.

@SCAR FINLEY TALLMAN. VILLIAM PAUL KIMBROUGH. LOUIS JAMES REYNOLDS.

